1. Field of the Invention
The present invention relates to a labor-saving type starter apparatus for an engine not provided with an automatic starter apparatus such as a cell starter.
2. Description of the Prior Art
As a labor-saving type starter apparatus to replace a reel type starting system for a small-sized internal combustion engine, a starter apparatus making use of a leaf spring of spiral shape as an energy accumulator has been disclosed in Laid-Open Japanese Patent Specification No. 58-51271 (1983).
The invention according to this patent application relates to a starter apparatus which can automatically start an engine through a starting operation of merely pulling a rod 116 by making use of an unnecessary torque upon stoppage of the engine in order to accumulate energy for starting as shown in FIGS. 33 and 34. The above-referred starter apparatus in the prior art illustrated in these figures is provided with a ratchet box 113 mounted on a baffle plate, supporting a starter shaft 107 concentric with a crank shaft 101 and accommodating therewithin a ratchet device for preventing the same starter shaft 107 from rotating in the reverse direction to the crank shaft 101. A power accumulator box 114 is rotatably supported from said starter shaft 107 and provided therein with a spiral spring 115 having its one end fixed to the same starter shaft 107 and the other end fixed to a circumferential wall. A starter pulley 102 is fixed to the crank shaft 101 and provided with a pin for supporting a claw 110 adapted to be engaged with and disengaged from a winding ratchet wheel 111 and a spring 110a for engaging the same claw 110 with the winding ratchet wheel 111 at the time of low speed rotation. A ratchet plate 109 is supported by the same starter pulley 102 so as to be displaceable in the circumferential direction with respect to the starter pulley 102 owing to an elongated hole in which the pin of the starter pulley 102 is inserted for disengaging the above-mentioned claw 110 from the winding ratchet wheel 111 by their relative displacement. A starter rod 116 is inserted into a hole formed in the above-mentioned power accumulator box 114 from the side of the above-described baffle plate for fixing the aforementioned power accumulator box 114, and a claw 106 of the power accumulator box 114 is provided in the aforementioned power accumulator box 114 and is adapted to be engaged with the above-mentioned ratchet plate 109 and starter pulley 102 as a result of rotation of the same power accumulator box 114. At the time of low speed rotation upon stoppage of the engine, by the claw 110 engaged with the winding ratchet wheel 111, the above-mentioned starter shaft 107 is interlocked with the aforementioned starter pulley 102. Thus power is accumulated by winding the spiral spring 115 in the power accumulator box 114 which is locked by the starter rod 116, but upon starting of the engine the aforementioned starter rod 116 is disengaged from the power accumulator box 114. Thus, the power accumulator box 114 is rotated by the power accumulated in the spiral spring 115 and is successively interlocked with the aforementioned ratchet plate 109 and starter pulley 102 by means of the claw of the power accumulator box 114, and the coupling between the above-mentioned starter pulley 102 and the aforementioned starter shaft 107 is blocked by the ratchet plate 109 so that the engine may be started by the rotation of the above-mentioned starter pulley 102.
According to the prior art as described above, since an inertial force upon stoppage of an engine is employed as an energy source for driving a power accumulator mechanism, in the general process of stopping an engine after an idling operation, shortage of energy will occur. In order to accumulate energy required for starting, the operation of raising a rotational speed of the engine before stoppage or the like is necessary. Therefore, the prior art apparatus is impractical to use.
In addition, in the event that one has failed in starting an engine by means of the above-described spiral spring type starter apparatus, as a power source for accumulating power in the power accumulator spring either an external electric power source or human labor is necessitated. Therefore, the apparatus is not always satisfactory as a labor-saving type starter apparatus.